assume cs:codesg

codesg segment
		
		mov ax,4c00h
		int 21h
		
	start: mov ax,0
	    s: nop
		   nop
		   
		   mov di,offset s
		   mov si,offset s2
		   mov ax,cs:[si]
		   mov cs:[di],ax
		
		s0: jmp short s
		
		s1: mov ax,0
		    int 21h
			mov ax,0
			
		s2: jmp short s1
		    nop
codesg ends

end start